EXTRACTIVES FROM BLACKBUTT (EUCALYPTUS-PILULARIS) WOOD WHICH AFFECT GLUEBOND QUALITY OF PHENOLIC RESINS

Blackbutt (Eucalyptus pilularis) is known as a high density and ''difficult to glue'' wood species, from which hot water extractives were obtained. The effect of the extractives on gelation of a phenolic resin was determined and was found to vary depending on the amount of the extractives added to the phenolic resin. Using authentic hydrolysable tannins, particularly ellagitannins isolated from Eucalyptus woods, separation of hydrolysable tannins by high performance liquid chromatography (HPLC) has been achieved by using NWP (acetonitrile-water-phosphoric acid) solvent systems on reversed phase ODS columns. The HPLC analysis of the hot water extractives from blackbutt revealed that the extractives consisted of ellagitannins D-1, D-4, D-6, D-13 and three unknown ellagitannins. Ellagitannin D-13 (28.3%) was found as the major component of the hot water extractives.